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Particular Configuration (particular + configuration)
Selected AbstractsNumerical analysis of a 3D hydrodynamic contactINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 12 2006Costin Alin Caciu Abstract We study here the numerical analysis of a hydrodynamic contact in a particular configuration: the 3D incompressible viscous flow of a fluid dragged by a smooth plate over a rough surface. The mathematical model takes into account and discretizes the local topography of the rough profile. The simulation outcome will be the 3D velocity and pressure fields of the fluid film within the contact borders. This work is limited to the study of numerical resolution methods working solely in finite differences. The algorithms will be tested by analysing and comparing their results with analytically known flows. Copyright © 2006 John Wiley & Sons, Ltd. [source] Effect of leading edge cut on the aerodynamics of ram-air parachutesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 1 2005R. Balaji Abstract The effect of the configuration of leading edge cut on the aerodynamic performance of ram-air parachutes is studied via two-dimensional flow simulations. The incompressible Reynolds-averaged Navier,Stokes equations, in primitive variables, are solved using a stabilized finite-element formulation. The Baldwin,Lomax model is employed for turbulence closure. Flow past an LS(1) 0417 airfoil is investigated for various configurations of the leading edge cut and results are compared with those from a Clark-Y airfoil section. It is found that the configuration of the leading edge cut affects the lift-to-drag ratio (L/D) of the parachute very significantly. The L/D value has strong implications on the flight performance of the parachute. One particular configuration results in a L/D value that is in excess of 25 at 7.5° angle of attack. Results are presented for other angles of attack for this configuration. Copyright © 2004 John Wiley & Sons, Ltd. [source] Spectroscopic study of the physical properties making trehalose a stabilizing and shelf life extending compound in food industryQUALITY ASSURANCE & SAFETY OF CROPS & FOOD, Issue 2 2010S. Magazł Abstract Introduction Trehalose, a glass-forming bioprotectant disaccharide, has been demonstrated to possess significant potential within the food industry. It does not interact with reactive molecules such as amino groups from peptides and proteins, preventing the degradation and aggregation due to Maillard reactions. Objective This paper aims to review at the molecular level the effects of trehalose on the structural and dynamical properties of water and on protein to highlight the stabilization and conservation properties on food products. Results and Conclusions The experimental findings presented show that water molecules are arranged in presence of trehalose in a particular configuration which avoids ice formation, so limiting damage due to freezing and cooling. On the other hand, homologous disaccharides, and trehalose to a greater extent, slow down the dynamics of water with a significant influence on the biological activity. These results imply that trehalose has a greater ability to bind volatile substances and deliver superior bioprotective effectiveness. Furthermore trehalose is shown to be incapable of taking part in the denaturation process of lysozyme under thermal stress. [source] On the modelling of over-ocean hurricane surface winds and their uncertaintyTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 642 2009Dr. S. P. Khare Abstract This paper investigates the modelling of over-ocean hurricane surface wind fields and their associated uncertainty. The wind models tested include parameterized balance models, a two-dimensional numerical planetary boundary-layer model and a three-dimensional (3D) linear analytical boundary-layer model. Using a set of archived over-ocean surface wind field reconstructions for validation, a series of cross-validation experiments has been performed for a range of norms. For norms that quantify predictability of vector fields, a particular configuration of the 3D analytical model was found to be superior to the other models tested. Using residual fields derived from fitting the wind models to the validation data, the issue of how to model the uncertainty (in the form of a covariance) in the speed field has also been examined. Covariance models based on truncated empirical orthogonal function representations were found to be optimal. Copyright © 2009 Royal Meteorological Society [source] Muscle moment arms of the gibbon hind limb: implications for hylobatid locomotionJOURNAL OF ANATOMY, Issue 4 2010Anthony J. Channon Abstract Muscles facilitate skeletal movement via the production of a torque or moment about a joint. The magnitude of the moment produced depends on both the force of muscular contraction and the size of the moment arm used to rotate the joint. Hence, larger muscle moment arms generate larger joint torques and forces at the point of application. The moment arms of a number of gibbon hind limb muscles were measured on four cadaveric specimens (one Hylobates lar, one H. moloch and two H. syndactylus). The tendon travel technique was used, utilizing an electro-goniometer and a linear voltage displacement transducer. The data were analysed using a technique based on a differentiated cubic spline and normalized to remove the effect of body size. The data demonstrated a functional differentiation between voluminous muscles with short fascicles having small muscle moment arms and muscles with longer fascicles and comparatively smaller physiological cross-sectional area having longer muscle moment arms. The functional implications of these particular configurations were simulated using a simple geometric fascicle strain model that predicts that the rectus femoris and gastrocnemius muscles are more likely to act primarily at their distal joints (knee and ankle, respectively) because they have short fascicles. The data also show that the main hip and knee extensors maintain a very small moment arm throughout the range of joint angles seen in the locomotion of gibbons, which (coupled to voluminous, short-fascicled muscles) might help facilitate rapid joint rotation during powerful movements. [source] Gender, Violence and Global Politics: Contemporary Debates in Feminist Security StudiesPOLITICAL STUDIES REVIEW, Issue 2 2009Laura J. Shepherd In this essay I develop a critique of the war/peace dichotomy that is foundational to conventional approaches to IR through a review of three recent publications in the field of feminist security studies. These texts are Cynthia Enloe's (2007) Globalization and Militarism, David Roberts' (2008) Human Insecurity, and Mothers, Monsters, Whores: Women's Violence in Global Politics by Laura Sjoberg and Caron Gentry (2008). Drawing on the insights of these books, I ask first how violence is understood in global politics, with specific reference to the gendered disciplinary blindnesses that frequently characterise mainstream approaches. Second, I demonstrate how a focus on war and peace can neglect to take into account the politics of everyday violence: the violences of the in-between times that international politics recognises neither as ,war' nor ,peace' and the violences inherent to times of peace that are overlooked in the study of war. Finally, I argue that feminist security studies offers an important corrective to the foundational assumptions of IR, which themselves can perpetuate the very instances of violence that they seek to redress. If we accept the core insights of feminist security studies , the centrality of the human subject; the importance of particular configurations of masculinity and femininity; and the gendered conceptual framework that underpins the discipline of IR , we are encouraged to envisage a rather different politics of the global. [source] Bond analyses of borates from the Inorganic Crystal Structure DatabaseACTA CRYSTALLOGRAPHICA SECTION B, Issue 5 2006Daqiu Yu Various fundamental building blocks (FBBs) are observed in the crystallographic structures of oxoborates available in the Inorganic Crystal Structure Database, Version 1.3.3 (2004); the occurrence of borate groups with low complexity is dominant. Bond-valence parameters d0 of B,O bonds in 758 oxoborates with various FBBs have been calculated using the bond-valence sum model. Some discrepancies in the d0 values obviously occur if the detailed configurations of FBBs in borate crystals are considered; d0 is sensitive to the chemical bonding structure of B atoms in the crystallographic framework. Moreover, d0 values are affected by the existence of interstitial atoms and the substitution of other anionic groups. In addition, the d0 parameters for B,N, B,S, B,P and B,F bonds are also calculated statistically. Some suitable d0 data for various borate FBBs are recommended according to their particular configurations, especially for those with low complexity. On the basis of the proposed linear relationship between calculated nonlinear optical (NLO) coefficients of borates and the current d0 values for various FBBs, it is found that the d0 values may be regarded as a useful parameter for pre-investigating the NLO properties of borates, leading to an efficient structural evaluation and design of novel borates. [source] | ||||||||||